Volatility is back thanks to geopolitical turmoil around the globe, and a pall has been cast over the merger boom thanks to a Harvard professor.

Paul Vigna

In the latest installment of MoneyBeat Week, our Friday podcast, the team digs into what’s driving the market’s latest swings. The Dow Jones Industrial Average surged 185 points on Friday, its biggest one-day gain in five months, after a report that Russia’s defense ministry ended military exercises near Ukraine.

But the rally capped a choppy week in which headline-driven trading made a comeback. After several big swings, the blue-chip Dow ended the week up 0.4%. It remains down for the year.

In addition, Harvard Law School professor Stephen Shay may have single-handedly crashed the corporate inversion party. He appears to be the first person to make the government aware of its powers to crack down on the advantageous tax treatment of inversions. His findings have sent chills through corporate boardrooms and law firms that have been profiting off the recent merger mania.

MoneyBeat’s Maureen Farrell, who has been all over this story, offers her latest findings on the podcast.